452 I'rof. J. C. Bose. On Electric Touch and the Molecular 



" On Electric Touch and the Molecular Changes produced in 

 Matter bv Electric Waves." By Jagadis Chuxder Bose, 

 M.A., D.Sc, Professor of Physical Science, Presidency 

 College, Calcutta. Communicated bv Lord PiAYLEIGH, F.E.S. 

 Eeceived January 29 —Bead February 8, 1900. 



\* In the various investigations on the properties of electric waves^ 

 one property has not yet attracted so much attention as it deserves — 

 the action of long ether waves in modifying the molecular structure 

 of matter. Apart from the interest attached to the relation between 

 ether, electricity, and matter, the subject is of importance as affording 

 not only a very important verification of the identit}" of "sasible and 

 electric radiation, l3ut also establishing the continuity of all radiation 

 phenomena. These phenomena occupy the borderland between physics 

 and chemistry, and their study may therefore be expected to throw 

 much light on several subjects at present imperfectly understood. The 

 study of the action of electricity and of ether waves on matter in the 

 form of solids presents many difficulties, owing to the great com- 

 plexity of atomic and molecular aggregation which characterises the 

 solid state of matter. But the phenomena often met with in theory 

 and practice is, unfortunately, in reference to matter in a solid state. 

 The means of investigation are almost wanting : chemical tests give 

 us no information, for they tell us (and that in a few cases only) of 

 the ultimate change in the mass as a whole, and not of the protean 

 transformations that are constantly taking place in it under the 

 action of ever- varying changes in physical environments. In the fol- 

 lowing investigations the difficulties mentioned above were constantly 

 present, and the attempts to meet them may therefore be of some 

 interest.] 



In my former paper f I described the contact-sensitiveness of various 

 elementary substances to electric rachation. It was shown that though 

 many substances exhibit a diminution of contact-resistance, there are 

 others which show an increase of resistance — an increase which, in 

 certain cases, lasts only during the impact of electric Ag aves, the sensi- 

 tive substance automatically recovering its original conductivity on the 

 cessation of radiation. There are thus produced two opposite effects, 

 either an increase or a diminution of resistance, depending on the nature 

 of the substance. 



The effect of increase of contact-resistance is not an exceptional or 

 isolated phenomenon, but is as normal and definite under varied con- 



* Matter in brackets [ ] added Marcli, 1900. 



t " On a Self-recovering Coherer, and the Study of the Cohering Action of 

 Different Metals," ' Eov. Soc. Proc.,' vol. 65. 



